BSA Owners' Club Forum

The BSA Workshop => Singles => Topic started by: TIGERJ on 05 August, 2017, 06:34:28

Title: C15 timing
Post by: TIGERJ on 05 August, 2017, 06:34:28
After much help and advice from members thanks again I am getting there with the carb. settings.
Decided to recheck ignition timing.
The adjusting plate is in fully advanced position BUT spark still needs advancing.
I am guessing distributor needs reposition on crank.
Can this be done without removing the gearbox outer cover.
Regards
           Tim
Title: Re: C15 timing
Post by: DEAN SOUTHALL on 05 August, 2017, 08:04:30
The procedure is set put in the BSA service sheet. A full set for download is here:-

http://www.bsaunitsingles.com/Archives/Owners_Manuals/C15%20&%20B40%20Service%20Sheets%20Book%2000-4082%20x.pdf
Title: Re: C15 timing
Post by: TIGERJ on 05 August, 2017, 10:37:10
Thanks Dean
                   Not sure if the procedure is the same for points on the side engine,which I have.
                    I may have misled you you by referring to the distributor.
However service sheets very useful, thanks.
Title: Re: C15 timing
Post by: JulianS on 05 August, 2017, 11:01:52
The auto advance/cam behind the points plate is fitted in a taper and can be removed and repositioned.
Title: Re: C15 timing
Post by: TIGERJ on 05 August, 2017, 14:38:20
Thanks Julian
I will try to find a way to exert a pull to the plate.
Without removing the g/box cover
Title: Re: C15 timing
Post by: JulianS on 05 August, 2017, 15:15:09
The points mounting plate should come away when you undo the 2 fixings, exposing the auto advance unit. Loosen the centre bolt but dont fully remove it and if you carefully tap to one side you will free unit from the taper and allow it to be removed. Hit it too hard you will bend the bolt.

There is special tool, an extractor bolt to do the job.
Title: Re: C15 timing
Post by: TIGERJ on 05 August, 2017, 17:14:52
Thanks Julian.
Will give it a try.
Title: Re: C15 timing
Post by: DEAN SOUTHALL on 05 August, 2017, 19:37:35
Thanks Dean
                   Not sure if the procedure is the same for points on the side engine,which I have.
                    I may have misled you you by referring to the distributor.
However service sheets very useful, thanks.

I thought both were covered in the sheets.
Title: Re: C15 timing
Post by: TIGERJ on 08 August, 2017, 18:16:27
Julian
Your method for timing plate worked a treat!!
Thanks
Is it refitted  with a firm hammer tap ?
Title: Re: C15 timing
Post by: JulianS on 08 August, 2017, 18:21:33
I would just tighten the bolt.
Title: Re: C15 timing
Post by: TIGERJ on 12 August, 2017, 06:30:51
Having mega problems getting the timing set.
I notice springs are slack on distributor plate.
Any idea where you can buy a set.
Or are loose springs OK ?
Regards
            Tim
Title: Re: C15 timing
Post by: TIGERJ on 12 August, 2017, 20:13:44
Reset the ignition timing.
But still running very poor.
Starts first or second kick but will not pull or rev
Running out of ideas.
Not sure what to try next
Boo Hoo
Tim

Title: Re: C15 timing
Post by: JulianS on 13 August, 2017, 09:59:31
The springs need to be strong hold the auto advance unit in the fully retarded position when engine at rest. Slack no good.
Title: Re: C15 timing
Post by: TIGERJ on 13 August, 2017, 17:38:26
Any idea where I can get some ?
Springs that is.
Title: Re: C15 timing
Post by: TIGERJ on 13 August, 2017, 17:47:55
Dean Just had a good read of the service sheets(thanks again)
You are quite correct they do cover all types of distributor.
The potential good news according to the info on sheets I have used the in correct advance
SHOULD BE
0.280 " before TDC
NOT 0.125" stated in the Haynes manual.
Let's see if this helps
Fingers crossed
Regards
           Tim
Title: Re: C15 timing
Post by: DEAN SOUTHALL on 13 August, 2017, 17:54:47
Good luck Tim
I know how frustrating all this can be but one day soon you'll be wizzing  along on her with a group of mates and this will all be a faint memory.
cheers Dean
Title: Re: C15 timing
Post by: SIE7RA on 13 August, 2017, 22:05:31
.280 is correct for fully advanced timing,Make sure the bob weights are fully open when setting timing by inserting something between them
Title: Re: C15 timing
Post by: TIGERJ on 14 August, 2017, 21:34:13
C15 update
Re-timing yet again to the latest advance
NO BETTER
Now convinced the problem is the advance springs
With engine at tickover slight increase in revs gives full centrifugal advance
So sure this is not correct
NEED NEW SPRINGS BUT CANNOT FIND A SUPPLIER
CAN ANYONE HELP
Tim
Title: Re: C15 timing
Post by: DEAN SOUTHALL on 14 August, 2017, 21:57:16
Have you thought of electronic ignition? Less than 100 for a Boyer for the C15 and once set up you can forget about it. No need for mechanical advance, points etc.
Title: Re: C15 timing
Post by: TIGERJ on 15 August, 2017, 06:12:06
Many thanks for your reply.
I may have to follow that route even though I spent on new 6v kit.
Title: Re: C15 timing
Post by: TIGERJ on 15 August, 2017, 06:25:31
Does anyone know if the if the advance springs on a distributor bike are the same as fitted
to the side points model ?
Or any associated part numbers ?
Or any specifications of the springs ?
Title: Re: C15 timing
Post by: JulianS on 15 August, 2017, 09:45:05
Photos below, first from 1964 Lucas Equipment for BSA, second the 1965 issue, third the parts fitted to BSA from 1965 issue.

Might help you figure out the spring numbers.

I would phone some of the larger dealers, C and D Autos for example.

You can see the distributor springs are different parts.

If your a/r is giving trouble electronic is the way to go.
Title: Re: C15 timing
Post by: DEAN SOUTHALL on 15 August, 2017, 10:26:34
Many thanks for your reply.
I may have to follow that route even though I spent on new 6v kit.

6V electronic ignitions are readily available.
Title: Re: C15 timing
Post by: TIGERJ on 19 August, 2017, 19:09:30
TODAY IS GREAT DAY
Decided to stick with the old set up for the time.
Side points advance springs are stocked by Greystone tiger cub parts.
With the new springs running much better BUT not revving much past 1/4
So to the carburettor
Some of you will remember I have an Amal 375 fitted to SS80
So jetting was experimental
Ended up with 180 main
With needle set to middle position running better than ever
Bike is now revving freely
MANY THANKS FOR ALL THE GREAT ADVICE
I remember Arther warning to expect engine problems
He was correct
Regards
           Tim